Heaviside’s dolphins (Cephalorhynchus heavisidii) occur only on the west coast of Southern Africa; they seem most abundant in waters less than 100 m deep, and are usually found in small groups seldom exceeding 10 animals.  They are seen infrequently and in small number, hence we believe it really is a rare species; although there are no reliable population estimates anywhere in the species’ range, and consequently its management status remains unresolved.  The species significance to global biodiversity, due to its endemism to the south-western African coast leaves far less doubts.  Direct threats to either the species or specific population(s) remain little known, although deliberate kills for human consumption were reported through late 1980s, as were incidental captures in fishing gear.  The latter, although infrequent, are still likely to occur.  Currently however, the issue of primary concern involving this species is our lack of knowledge of virtually all aspects of its ecology and behavioral biology.  Not only population figures remain unknown, but so are population structure, behavioral processes, social dynamics, and almost all aspect of their daily lives.

A recent telemetry study conducted by a graduate student from University of Pretoria (PhD project by S. Elwen) indicates that Heaviside's dolphins undertake a regular daily onshore-offshore movement, approaching the coast in early morning, and moving offshore in early afternoon; a pattern likely related to foraging and resting (or hiding from predators) strategies.  Furthermore, individual dolphins seem to have a spatially limited range and might exhibit a high degree of site fidelity.  However, much of the earlier work did not progress beyond a preliminary stage.  The apparently high degree of geographic fidelity would likely facilitate stronger social bonds and possibly genetic differentiation between distant groups; but the earlier photo-identification research and limited genetic data does not support such hypothesis.  There are many questions about Heaviside’s dolphins that have been asked for a long time, but very few have been answered, and even these limited preliminary answers are nowhere near complete and in fact somewhat confusing.  It is this evident lack of basic knowledge of an endemic and rare species that led us to undertake our current study.  Heaviside’s dolphins remain among the least known cetaceans, and unless this state of knowledge improves there is little that could be done for their conservation and stock management other than the wise use of the Precautionary Principle.  There is a clear and urgent need for data that covers a broad scope of conservation issues; that applies a large sampling effort and modern analytical techniques.  Our current project represents a first orchestrated step in that direction.

Apart of the abovementioned issues, never the ecological health of Heaviside’s dolphins has been addressed.  Similarly as sharks, dolphins are top predators of the marine ecosystems, and as such they are susceptible of building up significant concentrations of persistent pollutants that makes them potentially exposed to many adverse effects.  The knowledge of potential health risks associated with exposure to contaminants is essential to the formulation of effective conservation strategies.  By conducting a multifaceted and coordinated research in population ecology, socio-ecology, population genetics, eco-toxicology, and modelling of population dynamics, the present project will establish the current status and population structure of Heaviside’s dolphins, and their status of bio-contamination which, in a long-term, will provide quantitative basis for subsequent monitoring of the hazards posed by persistent pollutants. 

As a follow-up step, we intend to undertake a comparative assessment of the current status of contamination of other coastal dolphin species and sharks occurring in the South African region; this comparative dataset will be used as a measure of the ecological health of the ecosystem.  The present project represents a first step in a conservation-research effort that aims at addressing the fundamental issues in Heaviside’s dolphin ecology and conservation biology, a likely long-term endeavour that will contribute an important component to marine conservation in southern African region.